Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/power/user.c |
| 3 | * |
| 4 | * This file provides the user space interface for software suspend/resume. |
| 5 | * |
| 6 | * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> |
| 7 | * |
| 8 | * This file is released under the GPLv2. |
| 9 | * |
| 10 | */ |
| 11 | |
| 12 | #include <linux/suspend.h> |
| 13 | #include <linux/syscalls.h> |
Stefan Seyfried | 3592695 | 2006-12-06 20:34:06 -0800 | [diff] [blame] | 14 | #include <linux/reboot.h> |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 15 | #include <linux/string.h> |
| 16 | #include <linux/device.h> |
| 17 | #include <linux/miscdevice.h> |
| 18 | #include <linux/mm.h> |
| 19 | #include <linux/swap.h> |
| 20 | #include <linux/swapops.h> |
| 21 | #include <linux/pm.h> |
| 22 | #include <linux/fs.h> |
Rafael J. Wysocki | 97c7801 | 2006-10-11 01:20:45 -0700 | [diff] [blame] | 23 | #include <linux/console.h> |
Rafael J. Wysocki | e3920fb | 2006-09-25 23:32:48 -0700 | [diff] [blame] | 24 | #include <linux/cpu.h> |
Nigel Cunningham | 7dfb710 | 2006-12-06 20:34:23 -0800 | [diff] [blame] | 25 | #include <linux/freezer.h> |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 26 | |
| 27 | #include <asm/uaccess.h> |
| 28 | |
| 29 | #include "power.h" |
| 30 | |
| 31 | #define SNAPSHOT_MINOR 231 |
| 32 | |
| 33 | static struct snapshot_data { |
| 34 | struct snapshot_handle handle; |
| 35 | int swap; |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 36 | int mode; |
| 37 | char frozen; |
| 38 | char ready; |
Rafael J. Wysocki | 2b5b09b | 2007-02-10 01:43:35 -0800 | [diff] [blame] | 39 | char platform_suspend; |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 40 | } snapshot_state; |
| 41 | |
Rafael J. Wysocki | 0709db6 | 2007-05-06 14:50:45 -0700 | [diff] [blame] | 42 | atomic_t snapshot_device_available = ATOMIC_INIT(1); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 43 | |
| 44 | static int snapshot_open(struct inode *inode, struct file *filp) |
| 45 | { |
| 46 | struct snapshot_data *data; |
| 47 | |
Rafael J. Wysocki | 0709db6 | 2007-05-06 14:50:45 -0700 | [diff] [blame] | 48 | if (!atomic_add_unless(&snapshot_device_available, -1, 0)) |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 49 | return -EBUSY; |
| 50 | |
Rafael J. Wysocki | 1525a2a | 2007-05-06 14:50:44 -0700 | [diff] [blame] | 51 | if ((filp->f_flags & O_ACCMODE) == O_RDWR) { |
Rafael J. Wysocki | 0709db6 | 2007-05-06 14:50:45 -0700 | [diff] [blame] | 52 | atomic_inc(&snapshot_device_available); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 53 | return -ENOSYS; |
Rafael J. Wysocki | 1525a2a | 2007-05-06 14:50:44 -0700 | [diff] [blame] | 54 | } |
| 55 | if(create_basic_memory_bitmaps()) { |
Rafael J. Wysocki | 0709db6 | 2007-05-06 14:50:45 -0700 | [diff] [blame] | 56 | atomic_inc(&snapshot_device_available); |
Rafael J. Wysocki | 74dfd66 | 2007-05-06 14:50:43 -0700 | [diff] [blame] | 57 | return -ENOMEM; |
Rafael J. Wysocki | 1525a2a | 2007-05-06 14:50:44 -0700 | [diff] [blame] | 58 | } |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 59 | nonseekable_open(inode, filp); |
| 60 | data = &snapshot_state; |
| 61 | filp->private_data = data; |
| 62 | memset(&data->handle, 0, sizeof(struct snapshot_handle)); |
| 63 | if ((filp->f_flags & O_ACCMODE) == O_RDONLY) { |
Rafael J. Wysocki | 915bae9 | 2006-12-06 20:34:07 -0800 | [diff] [blame] | 64 | data->swap = swsusp_resume_device ? |
Rafael J. Wysocki | 7bf2368 | 2007-01-05 16:36:28 -0800 | [diff] [blame] | 65 | swap_type_of(swsusp_resume_device, 0, NULL) : -1; |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 66 | data->mode = O_RDONLY; |
| 67 | } else { |
| 68 | data->swap = -1; |
| 69 | data->mode = O_WRONLY; |
| 70 | } |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 71 | data->frozen = 0; |
| 72 | data->ready = 0; |
Rafael J. Wysocki | 2b5b09b | 2007-02-10 01:43:35 -0800 | [diff] [blame] | 73 | data->platform_suspend = 0; |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 74 | |
| 75 | return 0; |
| 76 | } |
| 77 | |
| 78 | static int snapshot_release(struct inode *inode, struct file *filp) |
| 79 | { |
| 80 | struct snapshot_data *data; |
| 81 | |
| 82 | swsusp_free(); |
Rafael J. Wysocki | 74dfd66 | 2007-05-06 14:50:43 -0700 | [diff] [blame] | 83 | free_basic_memory_bitmaps(); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 84 | data = filp->private_data; |
Rafael J. Wysocki | d1d241c | 2007-05-06 14:50:47 -0700 | [diff] [blame] | 85 | free_all_swap_pages(data->swap); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 86 | if (data->frozen) { |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 87 | mutex_lock(&pm_mutex); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 88 | thaw_processes(); |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 89 | mutex_unlock(&pm_mutex); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 90 | } |
Rafael J. Wysocki | 0709db6 | 2007-05-06 14:50:45 -0700 | [diff] [blame] | 91 | atomic_inc(&snapshot_device_available); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 92 | return 0; |
| 93 | } |
| 94 | |
| 95 | static ssize_t snapshot_read(struct file *filp, char __user *buf, |
| 96 | size_t count, loff_t *offp) |
| 97 | { |
| 98 | struct snapshot_data *data; |
| 99 | ssize_t res; |
| 100 | |
| 101 | data = filp->private_data; |
Rafael J. Wysocki | 2f41ddd | 2007-06-16 10:16:03 -0700 | [diff] [blame] | 102 | if (!data->ready) |
| 103 | return -ENODATA; |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 104 | res = snapshot_read_next(&data->handle, count); |
| 105 | if (res > 0) { |
| 106 | if (copy_to_user(buf, data_of(data->handle), res)) |
| 107 | res = -EFAULT; |
| 108 | else |
| 109 | *offp = data->handle.offset; |
| 110 | } |
| 111 | return res; |
| 112 | } |
| 113 | |
| 114 | static ssize_t snapshot_write(struct file *filp, const char __user *buf, |
| 115 | size_t count, loff_t *offp) |
| 116 | { |
| 117 | struct snapshot_data *data; |
| 118 | ssize_t res; |
| 119 | |
| 120 | data = filp->private_data; |
| 121 | res = snapshot_write_next(&data->handle, count); |
| 122 | if (res > 0) { |
| 123 | if (copy_from_user(data_of(data->handle), buf, res)) |
| 124 | res = -EFAULT; |
| 125 | else |
| 126 | *offp = data->handle.offset; |
| 127 | } |
| 128 | return res; |
| 129 | } |
| 130 | |
| 131 | static int snapshot_ioctl(struct inode *inode, struct file *filp, |
| 132 | unsigned int cmd, unsigned long arg) |
| 133 | { |
| 134 | int error = 0; |
| 135 | struct snapshot_data *data; |
Rafael J. Wysocki | af508b3 | 2007-10-26 00:59:31 +0200 | [diff] [blame^] | 136 | loff_t size; |
Rafael J. Wysocki | 3aef83e | 2006-12-06 20:34:10 -0800 | [diff] [blame] | 137 | sector_t offset; |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 138 | |
| 139 | if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC) |
| 140 | return -ENOTTY; |
| 141 | if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR) |
| 142 | return -ENOTTY; |
| 143 | if (!capable(CAP_SYS_ADMIN)) |
| 144 | return -EPERM; |
| 145 | |
| 146 | data = filp->private_data; |
| 147 | |
| 148 | switch (cmd) { |
| 149 | |
| 150 | case SNAPSHOT_FREEZE: |
| 151 | if (data->frozen) |
| 152 | break; |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 153 | mutex_lock(&pm_mutex); |
Rafael J. Wysocki | b10d911 | 2007-07-19 01:47:36 -0700 | [diff] [blame] | 154 | error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE); |
| 155 | if (!error) { |
Rafael J. Wysocki | 232b143 | 2007-10-18 03:04:44 -0700 | [diff] [blame] | 156 | printk("Syncing filesystems ... "); |
| 157 | sys_sync(); |
| 158 | printk("done.\n"); |
| 159 | |
Rafael J. Wysocki | b10d911 | 2007-07-19 01:47:36 -0700 | [diff] [blame] | 160 | error = freeze_processes(); |
| 161 | if (error) |
| 162 | thaw_processes(); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 163 | } |
Rafael J. Wysocki | b10d911 | 2007-07-19 01:47:36 -0700 | [diff] [blame] | 164 | if (error) |
| 165 | pm_notifier_call_chain(PM_POST_HIBERNATION); |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 166 | mutex_unlock(&pm_mutex); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 167 | if (!error) |
| 168 | data->frozen = 1; |
| 169 | break; |
| 170 | |
| 171 | case SNAPSHOT_UNFREEZE: |
Rafael J. Wysocki | 2f41ddd | 2007-06-16 10:16:03 -0700 | [diff] [blame] | 172 | if (!data->frozen || data->ready) |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 173 | break; |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 174 | mutex_lock(&pm_mutex); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 175 | thaw_processes(); |
Rafael J. Wysocki | b10d911 | 2007-07-19 01:47:36 -0700 | [diff] [blame] | 176 | pm_notifier_call_chain(PM_POST_HIBERNATION); |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 177 | mutex_unlock(&pm_mutex); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 178 | data->frozen = 0; |
| 179 | break; |
| 180 | |
| 181 | case SNAPSHOT_ATOMIC_SNAPSHOT: |
| 182 | if (data->mode != O_RDONLY || !data->frozen || data->ready) { |
| 183 | error = -EPERM; |
| 184 | break; |
| 185 | } |
Rafael J. Wysocki | 7777fab | 2007-07-19 01:47:29 -0700 | [diff] [blame] | 186 | error = hibernation_snapshot(data->platform_suspend); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 187 | if (!error) |
| 188 | error = put_user(in_suspend, (unsigned int __user *)arg); |
| 189 | if (!error) |
| 190 | data->ready = 1; |
| 191 | break; |
| 192 | |
| 193 | case SNAPSHOT_ATOMIC_RESTORE: |
Rafael J. Wysocki | 8357376 | 2006-12-06 20:34:18 -0800 | [diff] [blame] | 194 | snapshot_write_finalize(&data->handle); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 195 | if (data->mode != O_WRONLY || !data->frozen || |
| 196 | !snapshot_image_loaded(&data->handle)) { |
| 197 | error = -EPERM; |
| 198 | break; |
| 199 | } |
Rafael J. Wysocki | a634cc1 | 2007-07-19 01:47:30 -0700 | [diff] [blame] | 200 | error = hibernation_restore(data->platform_suspend); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 201 | break; |
| 202 | |
| 203 | case SNAPSHOT_FREE: |
| 204 | swsusp_free(); |
| 205 | memset(&data->handle, 0, sizeof(struct snapshot_handle)); |
| 206 | data->ready = 0; |
| 207 | break; |
| 208 | |
| 209 | case SNAPSHOT_SET_IMAGE_SIZE: |
| 210 | image_size = arg; |
| 211 | break; |
| 212 | |
Rafael J. Wysocki | af508b3 | 2007-10-26 00:59:31 +0200 | [diff] [blame^] | 213 | case SNAPSHOT_GET_IMAGE_SIZE: |
| 214 | if (!data->ready) { |
| 215 | error = -ENODATA; |
| 216 | break; |
| 217 | } |
| 218 | size = snapshot_get_image_size(); |
| 219 | size <<= PAGE_SHIFT; |
| 220 | error = put_user(size, (loff_t __user *)arg); |
| 221 | break; |
| 222 | |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 223 | case SNAPSHOT_AVAIL_SWAP: |
Rafael J. Wysocki | af508b3 | 2007-10-26 00:59:31 +0200 | [diff] [blame^] | 224 | size = count_swap_pages(data->swap, 1); |
| 225 | size <<= PAGE_SHIFT; |
| 226 | error = put_user(size, (loff_t __user *)arg); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 227 | break; |
| 228 | |
| 229 | case SNAPSHOT_GET_SWAP_PAGE: |
| 230 | if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { |
| 231 | error = -ENODEV; |
| 232 | break; |
| 233 | } |
Rafael J. Wysocki | d1d241c | 2007-05-06 14:50:47 -0700 | [diff] [blame] | 234 | offset = alloc_swapdev_block(data->swap); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 235 | if (offset) { |
| 236 | offset <<= PAGE_SHIFT; |
Rafael J. Wysocki | 3aef83e | 2006-12-06 20:34:10 -0800 | [diff] [blame] | 237 | error = put_user(offset, (sector_t __user *)arg); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 238 | } else { |
| 239 | error = -ENOSPC; |
| 240 | } |
| 241 | break; |
| 242 | |
| 243 | case SNAPSHOT_FREE_SWAP_PAGES: |
| 244 | if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { |
| 245 | error = -ENODEV; |
| 246 | break; |
| 247 | } |
Rafael J. Wysocki | d1d241c | 2007-05-06 14:50:47 -0700 | [diff] [blame] | 248 | free_all_swap_pages(data->swap); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 249 | break; |
| 250 | |
| 251 | case SNAPSHOT_SET_SWAP_FILE: |
Rafael J. Wysocki | d1d241c | 2007-05-06 14:50:47 -0700 | [diff] [blame] | 252 | if (!swsusp_swap_in_use()) { |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 253 | /* |
| 254 | * User space encodes device types as two-byte values, |
| 255 | * so we need to recode them |
| 256 | */ |
| 257 | if (old_decode_dev(arg)) { |
Rafael J. Wysocki | 7bf2368 | 2007-01-05 16:36:28 -0800 | [diff] [blame] | 258 | data->swap = swap_type_of(old_decode_dev(arg), |
| 259 | 0, NULL); |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 260 | if (data->swap < 0) |
| 261 | error = -ENODEV; |
| 262 | } else { |
| 263 | data->swap = -1; |
| 264 | error = -EINVAL; |
| 265 | } |
| 266 | } else { |
| 267 | error = -EPERM; |
| 268 | } |
| 269 | break; |
| 270 | |
Luca Tettamanti | 9b23820 | 2006-03-23 03:00:09 -0800 | [diff] [blame] | 271 | case SNAPSHOT_S2RAM: |
| 272 | if (!data->frozen) { |
| 273 | error = -EPERM; |
| 274 | break; |
| 275 | } |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 276 | if (!mutex_trylock(&pm_mutex)) { |
Luca Tettamanti | 9b23820 | 2006-03-23 03:00:09 -0800 | [diff] [blame] | 277 | error = -EBUSY; |
| 278 | break; |
| 279 | } |
Rafael J. Wysocki | 6c961df | 2007-07-19 01:47:38 -0700 | [diff] [blame] | 280 | /* |
| 281 | * Tasks are frozen and the notifiers have been called with |
| 282 | * PM_HIBERNATION_PREPARE |
| 283 | */ |
| 284 | error = suspend_devices_and_enter(PM_SUSPEND_MEM); |
Stephen Hemminger | a6d7098 | 2006-12-06 20:34:35 -0800 | [diff] [blame] | 285 | mutex_unlock(&pm_mutex); |
Luca Tettamanti | 9b23820 | 2006-03-23 03:00:09 -0800 | [diff] [blame] | 286 | break; |
| 287 | |
Stefan Seyfried | 3592695 | 2006-12-06 20:34:06 -0800 | [diff] [blame] | 288 | case SNAPSHOT_PMOPS: |
Rafael J. Wysocki | 2b5b09b | 2007-02-10 01:43:35 -0800 | [diff] [blame] | 289 | error = -EINVAL; |
| 290 | |
Stefan Seyfried | 3592695 | 2006-12-06 20:34:06 -0800 | [diff] [blame] | 291 | switch (arg) { |
| 292 | |
| 293 | case PMOPS_PREPARE: |
Rafael J. Wysocki | 7777fab | 2007-07-19 01:47:29 -0700 | [diff] [blame] | 294 | data->platform_suspend = 1; |
| 295 | error = 0; |
Stefan Seyfried | 3592695 | 2006-12-06 20:34:06 -0800 | [diff] [blame] | 296 | break; |
| 297 | |
| 298 | case PMOPS_ENTER: |
Rafael J. Wysocki | 7777fab | 2007-07-19 01:47:29 -0700 | [diff] [blame] | 299 | if (data->platform_suspend) |
| 300 | error = hibernation_platform_enter(); |
| 301 | |
Stefan Seyfried | 3592695 | 2006-12-06 20:34:06 -0800 | [diff] [blame] | 302 | break; |
| 303 | |
| 304 | case PMOPS_FINISH: |
Rafael J. Wysocki | 2b5b09b | 2007-02-10 01:43:35 -0800 | [diff] [blame] | 305 | if (data->platform_suspend) |
| 306 | error = 0; |
| 307 | |
Stefan Seyfried | 3592695 | 2006-12-06 20:34:06 -0800 | [diff] [blame] | 308 | break; |
| 309 | |
| 310 | default: |
| 311 | printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg); |
Stefan Seyfried | 3592695 | 2006-12-06 20:34:06 -0800 | [diff] [blame] | 312 | |
| 313 | } |
| 314 | break; |
| 315 | |
Rafael J. Wysocki | 37b2ba1 | 2006-12-06 20:34:15 -0800 | [diff] [blame] | 316 | case SNAPSHOT_SET_SWAP_AREA: |
Rafael J. Wysocki | d1d241c | 2007-05-06 14:50:47 -0700 | [diff] [blame] | 317 | if (swsusp_swap_in_use()) { |
Rafael J. Wysocki | 37b2ba1 | 2006-12-06 20:34:15 -0800 | [diff] [blame] | 318 | error = -EPERM; |
| 319 | } else { |
| 320 | struct resume_swap_area swap_area; |
| 321 | dev_t swdev; |
| 322 | |
| 323 | error = copy_from_user(&swap_area, (void __user *)arg, |
| 324 | sizeof(struct resume_swap_area)); |
| 325 | if (error) { |
| 326 | error = -EFAULT; |
| 327 | break; |
| 328 | } |
| 329 | |
| 330 | /* |
| 331 | * User space encodes device types as two-byte values, |
| 332 | * so we need to recode them |
| 333 | */ |
| 334 | swdev = old_decode_dev(swap_area.dev); |
| 335 | if (swdev) { |
| 336 | offset = swap_area.offset; |
Rafael J. Wysocki | 7bf2368 | 2007-01-05 16:36:28 -0800 | [diff] [blame] | 337 | data->swap = swap_type_of(swdev, offset, NULL); |
Rafael J. Wysocki | 37b2ba1 | 2006-12-06 20:34:15 -0800 | [diff] [blame] | 338 | if (data->swap < 0) |
| 339 | error = -ENODEV; |
| 340 | } else { |
| 341 | data->swap = -1; |
| 342 | error = -EINVAL; |
| 343 | } |
| 344 | } |
| 345 | break; |
| 346 | |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 347 | default: |
| 348 | error = -ENOTTY; |
| 349 | |
| 350 | } |
| 351 | |
| 352 | return error; |
| 353 | } |
| 354 | |
Helge Deller | 15ad7cd | 2006-12-06 20:40:36 -0800 | [diff] [blame] | 355 | static const struct file_operations snapshot_fops = { |
Rafael J. Wysocki | 6e1819d | 2006-03-23 03:00:03 -0800 | [diff] [blame] | 356 | .open = snapshot_open, |
| 357 | .release = snapshot_release, |
| 358 | .read = snapshot_read, |
| 359 | .write = snapshot_write, |
| 360 | .llseek = no_llseek, |
| 361 | .ioctl = snapshot_ioctl, |
| 362 | }; |
| 363 | |
| 364 | static struct miscdevice snapshot_device = { |
| 365 | .minor = SNAPSHOT_MINOR, |
| 366 | .name = "snapshot", |
| 367 | .fops = &snapshot_fops, |
| 368 | }; |
| 369 | |
| 370 | static int __init snapshot_device_init(void) |
| 371 | { |
| 372 | return misc_register(&snapshot_device); |
| 373 | }; |
| 374 | |
| 375 | device_initcall(snapshot_device_init); |